.mainContent {
  flex: 1;
  padding: 30px;
  background-color: #f5f9ff;
  border-left: 1px solid #e6f2ff;
  overflow-y: auto;
  height: calc(100vh - 70px);
}

/* 响应式设计 */
@media (max-width: 768px) {
  .mainContent {
    padding: 15px;
    height: calc(100vh - 60px);
  }
}